• Asian-Australasian Journal of Animal Sciences
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• v.22 no.2
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• pp.187-193
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• 2009

The present study identified the favorable conditions for isolation, enrichment and in vitro culture of highly purified, undifferentiated pig spermatogonial stem cell (SSC) lines that proliferate for long periods of time in culture. The colonies displayed morphology similar to miceSSC and were positive for markers of SSC (PGP9.5), proliferating germ cell (PigVASA), pre-meiotic germ cell (DAZL) and pluripotency (OCT4, SSEA-1, NANOG, and SOX2) based on immuno-cytochemistry and RT-PCR. The purity of these colonies was confirmed by negative expression of markers for sertoli cell (GATA4 and SOX9), peritubular myoid cell (${\alpha}$-SMA), differentiating spermatogonial and germ cells (c-KIT). The colonies could be maintained with undifferentiated morphology for more than two months and passaged more than 8 times with doubling time between 6-7 days. Taken together, we conclude that pigSSC could be successfully isolated and cultured in vitro and they possess characteristics similar to miceSSC.

• Journal of Chest Surgery
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• v.4 no.1
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• pp.25-34
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• 1971

We observed 88 csses of primary lung cancer clinically and statistically, which had been experienced at the dept. of thoracic surgery, St. Mary's Hospital, Catholic Medical College, during the period of 7 years from January, 1964 to December, 1970. The results obtained were as follows: 1) Peak incidence of age was from 5th decade to 7th decade (86.4%), the youngest being 25 and the oldest 76. The ratio of male to female was 4.9: 1. 2) Squamous cell carcinomas showed high resectability (68.7%) and short clinical duration (188 days). Adenocarcinoma and undifferentiated carcinoma showed low resectability (33.3%, 36.4%) in spite of the more shorter clinical duration(120 days, 112 days, respectively) than squamaus cell carcinoma. 3) Positivity (above class III) in brochocopic cytology was 70.3%, and 44.8% in fresh sputum cytology. 4) Other combined pulmonary diseases (emphysema. chronic bronchitis) were noted in about one half of bronchographied 66 cases and which were considered as factors to contribute ventilatory function of lung. 5) Among 88 cases, twelve cases refused operation and 34 cases(44.7%) were operated. Seventeen cases(22.3%) out of the 34 thoracotomies were resected, 7 with lobectomy and 10 with pneumonectomy and remaining 17 cases were unresectable. 6) Histopathological findiugs of resected 17 cases were squamous cell carcinomas (11 cases), adenocarcinoll1a(1 case), undifferentiated carcinumas (4 cases) and undetermined carcinoma(l case). 7) There's no opelative mortality. Among resected 17 cases, [; cases are still alive(4 years, 3 years & 2 mo, 2 yearo, 13 mo., respectively), 7 case were expired (3 of these from remote metastasis), and remaining 5 cases were unable to follow up.

• Journal of Periodontal and Implant Science
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• v.27 no.1
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• pp.111-116
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• 1997

The oral cavity is easily accessible for direct exposure of a malignant disease. 1 percent of the oral malignant tumors are of metastatic origin and approximately 10 percent to 25 percent of the 1 percent fraction originate from the lungs. A case of metastatic lung carcinoma to the gingiva in a 88-year-old male is reported. He complained of pain and swelling between right maxillary 1st premolar and 2nd molar. Although surgical excision of the lesion has been done, the gingival lesion developed as a quickly growing mass and recurred 2 weeks after surgical excision. The gingival mass was histopathologically diagnosed as an undifferentiated carcinoma. Epithelial layer was continuous without ulceration and it seems that the cancer cells are originated from primary tumor. Infiltrated cancer cells were pleomorphic and dyskeratotic. The cells had 2 or more nuclei, not showing squamous or glandular differentiation. Immunohistochemical study revealed the cells originated from the epithelial cells. The prognosis is poor, because prognosis depends on surgical elimination of the primary tumor.

• Korean Journal of Child Studies
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• v.15 no.1
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• pp.187-203
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• 1994

This study investigated the relation of androgynous parent's child-rearing practices to children's self-perceived competence by comparison of the effectiveness of androgynous people as parents compared with parents who are other-typed in their sex-role identity. The subjects were 362 third and sixth grade children and their parents selected from two elementary schools in Seoul. The instruments were a children's self-perceived competence scale, a perception of maternal warmth and control scale, a perception of paternal warmth and control scale, parent's self-esteem scale, and parent's sex-role identity scale. Frequencies, percentiles, mean, ${\chi}^2$ test, two way-ANOVA, one way-ANOVA, Cronbach's ${\alpha}$ and $Scheff{\acute{e}}$-test were used for data-analysis. The major findings showed that (1) Androgynous and masculine fathers had higher self-esteem than feminine or undifferentiated fathers. Androgynous, masculine, and feminine mothers had higher self-esteem than undifferentiated mothers. (2) There was no difference in children's perception of parental warmth and control as related to parent's sex-role identity. Androgynyous parents were not more likely to be authoritative parents. (3) Sons of androgynous parents had higher self-perceived competence than those of sex-typed parents, while daughters of sex-typed parents had higher self-perceived competence than those of androgynous parents.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.975-982
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• 2008

We investigated whether transplantation of osteogenically differentiated bone marrow-derived mesenchymal stem cells (BMMSCs) and the use of an hydroxyapatite (HAp) scaffold can enhance the in vivo bone formation efficacy of human BMMSCs. Three months after implantation to the subcutaneous dorsum of athymic mice, transplantation of osteogenically differentiated human BMMSCs increased the bone formation area and calcium deposition to 7.1- and 6.2-folds, respectively, of those of transplantation of undifferentiated BMMSCs. The use of the HAp scaffold increased the bone formation area and calcium deposition to 3.7- and 3.5-folds, respectively, of those of a polymer scaffold. Moreover, a combination of transplantation of osteogenically differentiated BMMSCs and HAp scaffold further increased the bone formation area and calcium deposition to 10.6- and 9.3-folds, respectively, of those of transplantation of undifferentiated BMMSCs seeded onto polymer scaffolds. The factorial experimental analysis showed that osteogenic differentiation of BMMSCs prior to transplantation has a stronger positive effect than the HAp scaffold on in vivo bone formation.

• Journal of The Korean Association For Science Education
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• v.29 no.5
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• pp.501-512
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• 2009

The purpose of this research is to compare the attitudes of female students in Korea toward science with the child-rearing attitude of their parents they perceived and their sex-role identity. The participants in this study were 374 female middle- and high-school students, chosen randomly from Seoul and Gyenggi-do in South Korea. We used three different forms of questionnaires in this research: "Scale of Parents' Child-rearing Behaviors Perceived by Teenagers", "Korea Sex-role Survey", and "Attitude Toward Science Measurement." The significant results were acquired after we had analyzed the comparison of the attitude of female students toward science with their perception on their parents' child-rearing attitude, especially on their fathers. The fathers' "monitoring" and "over-expectation" factors affected the attitudes of female students toward science; on the other hand, any child-rearing attitudes of their mothers did not influence their attitudes toward science. We also analyzed the attitudes of female students about science based on their sex-role identities. In consequence, we found that meaningful differences existed in four types of gender-role identity: androgyny type, masculinity type, femininity type and undifferentiated type. In particular, the androgyny type was characterized by a higher score in attitude toward science compared with the undifferentiated type.

• Journal of The Korean Association For Science Education
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• v.27 no.8
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• pp.677-692
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• 2007

In this study, university students were provided with repeated opportunities to represent their ideas graphically, and to examined via their drawings the extent to which they could visualize macroscopic phenomena microscopically. These drawings provided insight into the students' basic understanding of solution chemistry, revealing three conceptual models: the Undifferentiated Symbolic Model, the Particulate Model, and the Symbolic Ionic Model. Generally speaking, students who had poor conceptual understanding tended to exhibit the Undifferentiated Symbolic Model, whereas students with deeper understanding tended to employ the Symbolic Ionic Model. Students' conceptual comprehension was predictable from their graphical representations, which better elucidated what they actually comprehended about the phenomena, as opposed to their ambiguous verbal descriptions alone. The results of this study demonstrated a lack of development in university students' conceptions of solutions. Their weakness in understanding at the molecular-level became more obvious when they were asked to represent their ideas in drawings. Few students exhibited expert knowledge, and several common misconceptions were found, which indicated typical difficulties students have perceiving common phenomena at the molecular level. The findings of this study illustrate how eliciting graphical representations can be used to assess students' conceptual understandings.

• International Journal of Stem Cells
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• v.17 no.1
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• pp.38-50
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• 2024

Induced pluripotent stem cell (iPSC) technology has revolutionized various fields, including stem cell research, disease modeling, and regenerative medicine. The evolution of iPSC-based models has transitioned from conventional two-dimensional systems to more physiologically relevant three-dimensional (3D) models such as spheroids and organoids. Nonetheless, there still remain challenges including limitations in creating complex 3D tissue geometry and structures, the emergence of necrotic core in existing 3D models, and limited scalability and reproducibility. 3D bioprinting has emerged as a revolutionary technology that can facilitate the development of complex 3D tissues and organs with high scalability and reproducibility. This innovative approach has the potential to effectively bridge the gap between conventional iPSC models and complex 3D tissues in vivo. This review focuses on current trends and advancements in the bioprinting of iPSCs. Specifically, it covers the fundamental concepts and techniques of bioprinting and bioink design, reviews recent progress in iPSC bioprinting research with a specific focus on bioprinting undifferentiated iPSCs, and concludes by discussing existing limitations and future prospects.

• Development and Reproduction
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• v.4 no.2
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• pp.195-201
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• 2000

Sex differentiation process of the spotted sea bass, Lateolabrax maculatus, was investigated by histological method. The fish samples were collected from just after hatching to 365 days later. The primordial germ cells and genital ridge were appeared separately hanging under air bladder in 30-day larva (total length: 11.7~13.2 mm), and were unified into the undifferentiated gonads in 40-day larva (12.5~14.0 mm). The ovarian differentiation was started in 60-day juvenile (23.6~27.0 mm). The somatic tissues were elongated in tip of both ends of undifferentiated gonad and were fused each other. The complete ovarian cavity was appeared in 80-days juvenile(33.1~42.5 mm). The testicular differentiation was initiated in 70-day juvenile (24.8~31.6 mm). The rudiment of sperm duct was appeared in the center of the undifferentiated gonad. The meiosis of germ cells in the ovary was started in 168-day juvenile (88.0~115.4 mm). In 287-day juvenile (175.1~233.6 mm), the ovary was filled with both of chromatin stage and perinucleolus stage oocytes. The meiosis of male germ cells was started in 245-day juvenile (124.4~168.3 mm). However, the seminiferous tubules of testis were filled with numerous sperm in 365-day juvenile (162.5~253.8 mm). The sex ratio of male and female was 1:1.38. Considering these results, the spotted sea bass was showed differentiated type in sex differentiation and gonochorism in sexuality.

• Journal of Gastric Cancer
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• v.24 no.2
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• pp.172-184
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• 2024

Purpose: The original eCura system was designed to stratify the risk of lymph node metastasis (LNM) after endoscopic resection (ER) in patients with early gastric cancer (EGC). We assessed the effectiveness of a modified eCura system for reflecting the characteristics of undifferentiated-type (UD)-EGC. Materials and Methods: Six hundred thirty-four patients who underwent non-curative ER for UD-EGC and received either additional surgery (radical surgery group; n=270) or no further treatment (no additional treatment group; n=364) from 18 institutions between 2005 and 2015 were retrospectively included in this study. The eCuraU system assigned 1 point each for tumors >20 mm in size, ulceration, positive vertical margin, and submucosal invasion <500 ㎛; 2 points for submucosal invasion ≥500 ㎛; and 3 points for lymphovascular invasion. Results: LNM rates in the radical surgery group were 1.1%, 5.4%, and 13.3% for the low-(0-1 point), intermediate- (2-3 points), and high-risk (4-8 points), respectively (P-fortrend<0.001). The eCuraU system showed a significantly higher probability of identifying patients with LNM as high-risk than the eCura system (66.7% vs. 22.2%; McNemar P<0.001). In the no additional treatment group, overall survival (93.4%, 87.2%, and 67.6% at 5 years) and cancer-specific survival (99.6%, 98.9%, and 92.9% at 5 years) differed significantly among the low-, intermediate-, and high-risk categories, respectively (both P<0.001). In the high-risk category, surgery outperformed no treatment in terms of overall mortality (hazard ratio, 3.26; P=0.015). Conclusions: The eCuraU system stratified the risk of LNM in patients with UD-EGC after ER. It is strongly recommended that high-risk patients undergo additional surgery.